GTAForums user janmatant bought an Xbox 360 for €5 at a car boot sale, turned out to be a Rockstar North devkit with a 118GB GTA 4 beta build

[Mave]

Sources:

https://hiddenpalace.org/Grand_Theft_Auto_IV_(Nov_23,_2007_prototype)
https://gtaforums.com/topic/735829-grand-theft-auto-iv-beta-hunt/?do=findComment&comment=1072656468

This topic will serve as a collection of new discoveries from this GTA IV beta build.

 

[Mave]

They actually managed to restore ferries

 

[Mave]

Beta vs final map

 

[Mave]

Silenced pistol and baton